CAPACITOR DUTY CONTACTORS

Why special Capacitor Duty Contactor?
During the exact moment of switching, a capacitor effectively appears as short circuit. The magnitude of capacitor in-rush or charging current will depend upon value of AC Voltage level at instant of switching, together with impedence of feeders cable & supply transformers.

In case of individual capacitor loads, charging current peaks of upto 30 times the rated capacitor current can occur. Whereas, for multi-stage capacitor, the in-rush current greater than 180 times the rated capacitor current can occur.

Such large-current can flow through contactor since initial in-rush current is taken from both mains-supply & capacitor already connected. As in-rush current of such high magnitude is undesirable & likely to weld main contacts of Standard Duty Contactors.

It is, therefore, advisable to Limit the Current Surge by inserting quick discharge series damping resistence. Use Special Capacitor Duty Contactors.

Operating Principal
TC´s new Capacitors Duty Contactors are specially designed to meet Capacitor Duty applications. Contactor are fitted with block of three early make auxiliary contacts in series with quick discharge damping six resistors, 2 per phase to limit peak current to value within Contactor making capacity normal rated capacitor current is carried by main contacts which, after closing, effectively short out the resistors.

Product Range
Contactors 3P, 415V AC rating 10 KVAR thru 60 KVAR, available in eight ratings, conforming to IEC - 947 / IS 13947

Benefits

• Conforms to utilization category AC 6B as per IS 13947.
• Saves cost of expensive replacements.
• High electrical life.
• Reduced watt loss during ON condition, saves energy.
• High Safety.
• No risk of dangerous voltage.
• Switching of Capacitor bank in parallel without de-rating.
• Less maintenance & down-time.

Specification

Note:
(1) For TC1D12K-TC1D25K clip-on mounting into 35 mm. DIN rail / For TC1D33K-TC1D60K clip-on mounting into 75 mm. DIN rail
(2) Standard control circuit voltage.
(3) Average temperature over a 24-hour period, in accordance with IEC 70 and 831.